The invention relates to a composite foil, particularly a toilet seat support made from at least two layers in which at least one thin, outer, normally water-insoluble sealing layer is connected to a less thin, water-soluble supporting layer by means of one or more intermediate layers, as well as to a process and to an apparatus for producing this composite foil.
A toilet seat support formed from such a composite foil is known from DOS 2,703,005 of the present Applicant. In the manufacture of this toilet seat support, the individual layers of the composite foil are made by applying solutions of the foil materials to suitable substrates and evaporating the solvent. However, this process is relatively complicated and costly, because suitable evaporating equipment is required and also special precautions must be taken when handling organic solvents. It has also been found that the sealing layer does not have the desired freedom from pores due to the fact that bubbles form on evaporating the solvent from the sealing layer film, which leads to pores on drying.